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Abstract Piezoelectric semiconductors (PSs) simultaneously possess piezoelectricity and semiconducting properties. The polarization electric field resulted from piezoelectricity has a mechanically tuning effect on the transport behavior of charges in PSs. Such a phenomenon is called the piezotronic effect. With the exception of mechanical approach, one may use the magnetic field to control the piezotronic effect in piezoelectric semiconductors. It is a remote-controlled approach. In this paper, we propose a composite piezoelectric semiconductor cylindrical shell consisting of piezomagnetic and piezoelectric semiconductor layers. A polarization electric field is produced in the composite PS cylindrical shell under a magnetic field through the magnetoelectric coupling effect, and thus the magnetic field has a tuning effect on the piezotronic behavior of the composite PS cylindrical shell. We carry out an analysis on an infinite composite PS cylindrical shell under a constant radial magnetic field. The considered problem belongs to a plane strain problem, and all physical fields in the composite shell are only dependent on the radial position. To obtain the analytical solution and make a comparison, we employ the one-way coupled method and the linear fully-coupled method in this paper. The one-way coupled method neglects the effect of free charges on the polarization electric field. For the linear fully-coupled method, we assume that charges in the PS layer have a small perturbation, and thus the nonlinear drift current term can be linearized. We present analytical expressions of the physical fields in the composite PS shell including the displacement, the electric potential, and the carrier concentration. The influences of magnetic field as well as the thickness ratio between the PS layer and the shell on the piezotronic coupling effect in the composite PS shell are studied. The numerical results show that the magnetic field and the thickness ratio play an important role in tuning the piezotronic effect of the piezoelectric semiconductor layer. At the same time, it also provides a theoretical guidance for the design of piezoelectric semiconductor devices.
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Received: 29 October 2019
Published: 12 June 2020
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2020, Vol. 41 
